The international EUROPA stamp issue gets a new common theme every year. Generally, the European postal organization, Posteurop, whose members consist of 40+ postal organizations, determines the theme each year. Individual members then decide themselves which motifs they will use on their own stamps.
The theme of the EUROPA 2012 stamps is tourism. Belgium is one of the first countries issuing EUROPA stamp in 2012. Visit Belgium stampsheet was designed by Ever Meulen.